Objective:To investigate the risk factors for biochemical recurrence after radical prostatectomy.Methods:The clinical data of 558 radical prostatectomy patients admitted to the First Affiliated Hospital of Air Force Military Medical University from January 2010 to December 2020 were retrospectively analyzed. The average age was 67.9 (40-87) years old, and the average body mass index was 24.56 (15.12-35.94) kg/m 2. The average PSA was 41.07 ng/ml, including 48 cases<10 ng/ml, 98 cases 10-20 ng/ml, and 412 cases>20 ng/ml. There were 123, 214, 118, 89, and 14 cases with biopsy Gleason 6-10 score, respectively. The clinical stage : 90 cases in ≤T 2b, 273 cases in T 2c, and 195 cases in ≥T 3 . 558 cases underwent radical prostatectomy, including 528 robotic-assisted laparoscopic surgery, 25 laparoscopic surgery, and 5 open-surgery. The risk factors for postoperative biochemical recurrence were analyzed by Cox regression. Results:A total of 63 patients had postoperative pathological stage pT 2a, 32 patients had pT 2b, 241 patients had pT 2c, and 222 patients had ≥pT 3. A total of 210 cases developed biochemical recurrence after surgery, and the mean time to biochemical recurrence was 33.3 (3-127) months after the radical prostatectomy. The biochemical recurrence rates at 1, 3, and 5 years were 9.7% (54/558), 21.5% (120/558), and 31.7% (177/558), respectively. Among pT 2a and pT 2b patients, 7 (11.1%) and 4 (12.5%) cases developed biochemical recurrence, respectively. Among pT 2c stage patients, 145 (60.17%) cases had positive cut margins, treated with androgen-deprivation therapy (ADT) after surgery. 68 (28.21%) cases of pT 2c stage patients had biochemical recurrence at mean 36.1 (3-106)months after the radical prostatectomy. Among ≥pT 3 patients, 147 patients with positive margins, perineural invasion, seminal vesicle invasion and positive pelvic lymph nodes were treated with postoperative androgen deprivation therapy (ADT) + radiotherapy. 98 of 147 patients (66.67%) had biochemical recurrence, and the average time to biochemical recurrence was 30.6 (24-98) months.75 patients of ≥pT 3 without positive margins, perineural invasion, seminal vesicle invasion or positive pelvic lymph nodes, were treated with postoperative ADT. 33 of them (44%) had biochemical recurrence, and the average time to biochemical recurrence was 32.5 (21-106) months. 5-and 10-year survival rates of 210 patients with biochemical recurrence were 89.05% (187/210) and 78.09% (164/210) respectively, 5- and 10-year tumor-specific survival rates were 92.57% and 87.69%, respectively. 46 of 210 cases died, of which 31 (67.39%) died from prostate cancer, and 15 cases (32.61%) died from cardiovascular and cerebrovascular diseases. Multifactorial Cox regression analysis showed that patient's age ≥70 years, initial PSA > 20ng/ml, ≥pT 3 and Gleason score ≥7 were independent risk factors for biochemical recurrence. Conclusions:After radical prostatectomy, patients were treated according to their pathological stage and surgical margins. Patients with positive margins have a higher risk of biochemical recurrence. The independent risk factors for biochemical recurrence included age ≥70 years, initial PSA > 20ng/ml, ≥pT 3 and Gleason score ≥7.